Eosinophilic gastrointestinal disorders (EGIDs) constitute a diverse spectrum of disorders that affect one or more parts of the gastrointestinal (GI) tract and are characterized by increased numbers of eosinophils in one or more parts of the wall of the affected GI segment(s) (Rothenberg, M. J. Allergy Clin. Immunol. 113:11-28 (2004); Talley, N. et al. Gut 31:54-8 (1990)). EGIDs include eosinophilic esophagitis (EoE, also referred to as EE in some publications), eosinophilic gastritis (EG), eosinophilic duodenitis (ED), eosinophilic jejunitis (EJ), eosinophilic ileitis (EI), and eosinophilic colitis (EC).
The EGID that has been studied the most is EoE, partly because the diagnosis is made with increasing frequency (Furuta, G. et al. Gastroenterology 133:1342-63 (2007)). Other EGIDs, such as EG, have been less well-studied than EoE, and diagnostic criteria are less well-established than for EoE. EG and EoE represent diseases characterized by accumulation of eosinophils in the stomach or esophagus, respectively.